Air cylinder



FIG. 1 shows a front view of an air cylinder showing my new design;

FIG. 2 shows a rear view thereof;

FIG. 3 shows a right side view thereof;

FIG. 4 shows a left side view thereof;

FIG. 5 shows a top view thereof;

FIG. 6 shows a bottom view thereof;

FIG. 7 shows a bottom, front and left side perspective view thereof; and,

FIG. 8 shows a top, rear and right side perspective view thereof.

The broken lines in FIG. 5 are included for the purpose of illustrating portions of the air cylinder that form no part of the claimed design. 

The ornamental design for an air cylinder, as shown and described. 